The ETravelSim Poland eSIM works on PKP Intercity trains across the Warsaw-Krakow Express corridor with consistent 4G coverage on most segments. Routes between Warsaw, Wrocław, Gdansk, and Poznań stay connected on main lines. Brief drops are normal in deeper rural tunnels and forested stretches where Polish railway tracks pass through uninhabited areas, but signal returns before the next station. The PKP Intercity mobile app and Koleo work fluidly throughout for live platform changes, ticket QR codes, and connection updates.